Device for treatment of valve regurgitation

ABSTRACT

A device for treatment of valve regurgitation is described, comprising frameworks ( 114, 133, 141, 701, 812, 821, 911 ) and an anchoring unit ( 132 ). The anchoring unit ( 132 ) is connected to the frameworks ( 114, 133, 141, 701, 812, 821, 911 ); the frameworks ( 114, 133, 141, 701, 812, 821, 911 ) can be expanded and compressed and have an inflow end ( 421 ) and an opposite outflow end ( 422 ); valve leaflets ( 142, 621, 721, 751 ) capable of opening and closing in blood flow are provided inside the frameworks ( 114, 133, 141, 701, 812, 821, 911 ); the anchoring unit ( 132 ) can keep the frameworks ( 114, 133, 141, 701, 812, 821, 911 ) in an expanded state at the orifice position of a natural heart valve. The device for treatment of valve regurgitation and an implantation method therefor can effectively treat valve regurgitation.

TECHNICAL FIELD

The present disclosure pertains to the field of cardiovascular medical devices, and in particular to an implantable device for treating heart valve regurgitation, and methods of implanting the same.

BACKGROUND OF THE INVENTION

A mammalian heart contains four chambers as shown in FIG. 1, two atriums as the chambers for inflowing and two ventricles as the chambers for pumping out. The left ventricle 3 is located at the top left of apex 5, the mitral valve 2 is located between left atrium 1 and left ventricle 3, and the mitral valve 2 controls the unidirectional flow of blood from left atrium 1 to left ventricle 3. A dysfunctional mitral valve 2 will render two leaflets of the mitral valve 2 to close incompletely, causing blood to backflow from left ventricle 3 to left atrium 1 during systole. Mitral regurgitation will cause pulmonary congestion and hypertrophy of left ventricle 3, eventually leading to heart failure and death in patients. The structure of the mitral valve is shown in FIG. 2, which is a complex pressure-bearing one-way valve structure consisting of valve annulus 2.1, anterior valve leaflet 2.2, posterior valve leaflet 2.3, chordae 2.4, papillary muscle 2.5 and myocardium of the left ventricular wall. The papillary muscle is attached to the left ventricular wall 2.5; anterior valve leaflet 2.2 and posterior valve leaflet 2.3 are attached to the valve ring 2.1. The valve annulus 2.1 is an internal tissue structure connecting anterior leaflet 2.2, posterior leaflet 2.3 and the left ventricular wall. Depending on the tissue structure, valve annulus 2.1 is divided into a fibrous layer at the anteromedial segment and a muscle layer at the posterolateral segment. Chordae 2.4 is started from papillary muscle 2.5, and is attached to the leaflets, to prevent anterior valve leaflet 2.2 and posterior valve leaflet 2.3 from collapsing into the left atrium during systole.

The status of a functionally normal mitral valve when closed is shown in FIGS. 3a 1 and 3 a 2; there is no gap between anterior valve leaflet 2.2 and posterior valve leaflet 2.3 after the mitral valve is closed. It should be completely closed at the anterior and posterior valve leaflet junction 2.6, and will not cause regurgitation phenomenon. When the state of the mitral valve 2 is closed as shown in FIGS. 3b 1 and 3 b 2, there is a gap at the anterior and posterior leaflet junction 2.6 of the mitral valve 2, and the gap at the anterior and posterior leaflet junction 2.6 allows blood backflow from left ventricle 3 to left atrium 1 (backflow direction as shown by the arrows in FIG. 3b 1) during systole. The backflow is called mitral regurgitation.

The dysfunctional mitral valve causes incomplete closing of two valve leaflets of the mitral valve, making blood backflow from the left ventricle to the left atrium during systole. Mitral regurgitation will cause pulmonary congestion and left ventricular hypertrophy, eventually leading to heart failure and death of patients, so mitral regurgitation is a serious health disease. There are a large number of patients, conservatively estimated to be more than 100 million, who suffer from mitral regurgitation. Current treatments to repair valves include surgical operation, or in some cases, valve replacement when it is impossible to repair. However, there is no practical way to treat mitral regurgitation in patients who are unsuitable for thoracotomy or open heart surgery.

In recent years, many new technologies have been developed to meet this need. The MitraClip on the market is a proven repair device for the treatment of mitral regurgitation, but it is only suitable for relatively few patients, usually those patients with regurgitation caused by mitral valve prolapse, who still have residual regurgitation, whereas for patients with ischemic mitral regurgitation, the treatment is not effective. Furthermore, the sub-annular structure may enlarge and calcify, have a risk of chordal rupture chordal rupture. Most mitral valve repair techniques rely on minimally invasive devices to simulate surgical valve repair, such as restriction of mitral valve annulus by means of experimental instruments or relocation of papillary muscles and chordal repair by using instruments.

Interventional prosthetic valve replacement methods also have numerous difficulties, such as the placement of an anchoring device on an expanded native valve annulus, which can sometimes cause the annulus to expand further. Large valves often reduce durability of prosthetic valves significantly. With regard to those methods for reducing the size of the dilated annulus, an interventional annuloplasty ring in the minimally invasive prosthetic devices is less stable than its application of open-heart operation. Therefore, suitable replacement/anchoring devices are all very challenging and affect the application efficacy of this device. All of the devices described above have one thing in common: these minimally invasive methods of treating valve regurgitation have significant, unpredictable effects on native structures of valves and valve annuli. The technique of minimally invasive mitral or tricuspid valve plugging has the advantage of minimal interference with the native valve structure by placing plugs or plates in the regurgitation area where the native mitral or tricuspid valve leaflets cannot close to prevent backflow, whereas, the valve plug or plate will increase the flow resistance of the valve when it opens, resulting in a narrowing of valve orifice or in a more serious case, stenosis causes the risk of increased thrombosis in patients.

Due to the special physiological structure and complex physiological environment of the mitral annulus and tricuspid annulus, relevant treatment has great difficulties in achieving relatively good therapeutic effect, as well as positioning and fixation at the same time. In view of the problem treating mitral and tricuspid insufficiency in the prior art, transcatheter prosthetic valve replacement requires a large anchoring ring, affects the service life of the prosthetic valve and affects the function of the valve itself; although valve plug coaptation plate technology can prohibit backflow effectively, it would restrict the flow of blood when the valve opens, resulting in mitral or tricuspid stenosis, and increasing risk of thrombosis in patients. Therefore, it is necessary to explore a more effective and safe technique for treating mitral or tricuspid insufficiency.

SUMMARY OF THE INVENTION

In view of the above technical problem, by placing a device with a prosthetic valve at the native valve orifice, during systole the present disclosure provides an occluder to block the native valve leakage orifice; during diastole, the native valve and the prosthetic valve allows maximum effective orifice area for the blood inflow to prevent mitral/tricuspid stenosis. Through an anchoring system, the device provides an effective method for treating valve regurgitation, especially mitral or tricuspid regurgitation without device permanently adhering the native valve annulus or leaflets.

According to a first aspect of the present disclosure, a device for treating valve regurgitation, characterized in that it comprises a frame and an anchoring device, the anchoring device is engaged to a frame, the frame is expandable and compressible, having an inflow end and an outflow end, a prosthetic valve that opens and closes in the blood flow is provided inside the frame; and the anchoring device is capable of positioning the frame in an expanded state in the native heart valve orifice. When the native valve is closed, the native valve leaflets are in contact with the outer surface of the frame and form hemostatic seal; when the native valve is opened, the frame in the expanded state can translate freely within the orifice of the native valve, the prosthetic valve inside the frame is also open. When the device is applied to the mitral valve or tricuspid position, the frame is maintained by the anchoring device inside the native valve annulus along with the blood flow direction from the atrium to the ventricle in the long axis, and is self-adaptive to the coaptation force of the native valve leaflets in the cardiac short axis direction.

Preferably, the frame has an expandable and compressible lattice structure, and a covering membrane is provided on at least part of the inner and/or outer surface of the frame; the covering membrane must cover segment of the outer surface of the frame where the prosthetic valve leaflets are positioned.

Preferably, the frame has rhombic and/or hexagonal meshes, or the lattice structure is made of irregular meshes with curved edges of straight and arcuate lines. The material of the frame includes elastic metal material, elastic polymer material or memory alloy material. The frame may be formed by an integral laser cutting technique, a 3D printing technique or weaved from a wire material.

Preferably, all or part of the reinforcement is provided in the interior of the frame; the reinforcement includes a plate-like member, a column-like member, or a plate-like member or a column-like member with a lattice structure.

Preferably, the length in the cardiac long-axis direction from the inflow end to the outflow end of the expanded frame is 20-80 mm.

When the frame is expanded in the native valve orifice, the internal cross-section of frame is parallel to the cardiac short axis plane, or perpendicular to the cardiac long axis. Preferably, the cross-section at the cardiac short axis plane has a height of 3-30 mm and a width of 1-50 mm. The length, width, height of frame can be defined to fit the patient's native valve orifice.

Preferably, a cross-section of the frame at the cardiac short axis plane includes the following shape: circular, oval, rectangular or rounded rectangle, crescent or rounded crescent, dumbbell-shaped, a combination of a rectangle in the middle with semi-circular ends on opposing sides, a trapezoid or rounded trapezoid, and their combined shapes, or an overall shape similar to crescent as a whole with arcuate line in the middle and thicker in the middle than in two ends. The shape of such cross-section can be symmetrical or asymmetrical.

Preferably, the shape of a cross-section of the frame at the cardiac short-axis plane changes continuously or in stages from the inflow end to the outflow end of the frame.

Preferably, the covering membrane is attached to the frame by means of sintering, welding, gluing or sewing; the covering membrane covers the outer and inner surface of the frame where the prosthetic valve leaflets are positioned. The length of the outer covering membrane is less than or equal to the length of the frame; so is the inner covering. The inner covering preferably extends from junction of prosthetic valve leaflets towards ventricle end of the frame. The length of the covering membrane from the inflow end to the outflow end along the frame is 5-60 mm. The covering membrane is made of blood compatible material, such as artificial blood vessel material, animal valve, animal pericardium, and high molecular polymer.

Preferably, the prosthetic valve design includes a single-leaflet, a double-leaflet, a tri-leaflet or a quadro-leaflet configuration; the prosthetic valve leaflet is sewed or glued to the covering membrane or the frame. The material of the valve leaflets includes animal valves, animal pericardium, artificial chordae, polymer and artificial blood vessel material.

Preferably, the free edge of the prosthetic valve leaflet connected to a connector; the connector is connected to the frame and/or the covering membrane; structure of the connector includes strip, filament, sheet, column, net, or a combination thereof. The free edge of the prosthetic valve leaflets is held by the connector to facilitate coaptation without leaflet prolapse. The connector can be made of an animal valve, animal pericardium, artificial chordae, polymer or artificial blood vessel material. The connector can be made integrally with the prosthetic valve leaflets.

The anchoring device is to position the frame in the orifice of native valve. Preferably, the anchoring device comprises a linker and an anchor; the anchor is connected to the frame through the linker; the anchor may be arranged on the valve annulus, at the apex or between the papillary muscles near the apex, a stent and/or an anchor arranged on the surface of inner wall of ventricle, an open cup-shaped stent arranged in the inner chamber of atrium, an anchor arranged on the surface of the inner wall of atrium, a frame having a lattice structure arranged in the inner chamber of atrium, or a combination of the above anchors; the linker includes a rod, a wire, a sheet, a column, or a tube, or a combination thereof. The material of the linker includes an elastic metal material, a memory alloy material, or an elastic polymer material. The linker can be integrally manufactured as extension from an outflow end of the frame. The linker may have a blood compatible coating or covering.

Preferably, the linker and the anchor are connected by an elastic material or a hinge with certain degree of freedom; so the anchoring device allows swinging or rotating the frame in the native valve orifice. When the anchor is arranged at the apex or between the papillary muscles near the apex, an apex snap ring is provided outside of apex for preventing the anchor from moving, and the snap ring can bear the tension and pressure from the linker.

Preferably, the anchoring device comprises a supporting rod (a linker design), a positioning sleeve, an apex snap ring and a fixation plug; the proximal end of the supporting rod is connected to the outflow end of the frame; the distal end of the supporting rod is connected to the positioning sleeve; the apex snap ring is fixed at the apex or between the papillary muscles near the apex; the positioning sleeve is fixed on the apex snap ring; the fixation plug is connected to the apex snap ring and is located outside the apex to position the apex snap ring; the positioning sleeve can be moved or slid relative to the supporting rod. Preferably, the way of connecting the supporting rod to the anchor comprises an elastic connection or a hinge connection.

Preferably, the supporting rod is provided with a bend of 0-30 degrees from the proximal end to the distal end, and then connected with the anchor, the angle of the bend may also have additional movement in reference to the long axis in a range of 1-20 degrees or in a range of 5-10 degrees depending on the supporting rod to anchor connection mechanism.

In a second aspect, the technical solution of the present disclosure provides a method for implanting a device for treating valve regurgitation, wherein an expandable and compressible frame is compressed and loaded in a cannula, then is implanted into the native valve position through a minimally invasive technique to make the frame reach an expanded state, the frame is positioned at the native valve orifice by means of the anchoring device connected to the frame, such that the native heart valve leaflets coaptate on the outer surface of the frame; the anchoring device is compressed into the cannula and implanted into the heart, either simultaneously with the frame or not; the frame and the anchoring device may be completely retracted or partially retracted by the original implantation method.

Preferably, a method for implanting a device for treating valve regurgitation comprises the following steps:

a. an expandable and compressible frame, the linker and the anchor are collectively or partly assembled in vitro, whole assembly or subassembly may be compressed into a puncturing catheter;

b. the puncturing catheter is punctured from the apex position through an incision on left chest into the left ventricle or right ventricle, to the mitral or tricuspid valve orifice, the frame assembly is then pushed out, the puncturing catheter is withdrawn.

c. the anchor is attached to the apex position.

In a third aspect, the present disclosure provides the use of any of the above described devices and/or methods for treating valve regurgitation which specifically refers to mitral regurgitation and/or tricuspid regurgitation.

The technical benefits of the present disclosure are as follows: (1) The device of the present disclosure has prosthetic valve inside the occluder, comparing with a occluder, it reduces the flow resistance during diastole, and effectively decrease the risk of thrombosis; the native heart valve leaflets coaptate on the outer surface of the occluder and the prosthetic valve in the occluder also closes during systole, therefore the device has minimal interference with the native valve annulus for better ventricular function. (2) The device of the present disclosure has the advantages of simple structure, accurate positioning, small size, is suitable for various types of mitral/tricuspid regurgitation patients; by designing appropriately with minor modification of sizing, it can be used in children to high-risk elderly patients and is also applicable for treatment of valve prolapse. (3) The device of the present disclosure has little interference with the native valve annulus, it also helps to shorten the learning process for surgeon who often needs to correctly engage other devices to the native valve annulus.

The concept, specific structure and technical effects of the present disclosure will be further described below with reference to the following drawings to fully understand the objectives, features and effects of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the human heart anatomy, in which 1: left atrium, 2: mitral valve, 3: left ventricle, 4: aortic valve, 5: apex.

FIG. 2 is an enlarged schematic view of the tissue structure of mitral valve 2 in FIG. 1, wherein 2.1: annulus, 2.2: anterior leaflet, 2.3: posterior leaflet, 2.4: chordae, 2.5: papillary muscles.

FIG. 3 are schematic views of the mitral valve as shown in FIG. 2 that is closed normally and closed insufficiently during systole. FIG. 3a 1 is the right side view of the mitral valve when it is closed normally; FIG. 3a 2 is a partial enlarged view of the atrial side when the mitral valve is normally closed; FIG. 3b 1 is a right side view of mitral regurgitation when mitral valve is closed insufficiently; FIG. 3b 2 is a partial enlarged view of the atria side of mitral regurgitation when mitral valve is closed insufficiently, wherein 2.1: annulus, 2.2: anterior leaflet, 2.3 anterior leaflet, 2.4 chordae, 2.5: papillary muscles, 2.6: anterior/posterior leaflet closure/orifice.

FIG. 4 provides schematic views of the frame according to Embodiment 1. FIG. 4a 1 is a schematic perspective view of the frame; FIG. 4a 2 is a front view of FIG. 4a 1, FIG. 4a 3 is a side view of FIG. 4a 1, FIG. 4a 4 is a top view of FIG. 4a 1; FIG. 4b 1 is a perspective view of the frame in which mesh shape of the frame are changed, wherein, 411: frame length, 412: frame height, 413: frame width, 421: inflow end, 422: outflow end.

FIG. 5 provides schematic views of the frame according to Embodiment 1 provided with a reinforcement. FIG. 5a 1 is a schematic perspective view with a reinforcement in the center, and FIG. 5a 2 is a front view of FIG. 5a 1.

FIG. 6 provides schematic views of the frame with prosthetic valve leaflets. FIG. 6a 1 is a schematic view of single-leaflet valve leaflet sewn directly to the frame, FIG. 6a 2 is a top view of FIG. 6a 1; FIG. 6b 1 is a schematic view of single-leaflet valve leaflet held by the connector, FIG. 6b 2 is a front view of FIG. 6b 1, FIG. 6b 3 is a top view of FIG. 6b 1, FIG. 6b 4 is a side view of FIG. 6b 1; wherein 611 is a root of valve leaflet, 612 is the free edge of a valve leaflet, 621 is a valve leaflet body, 622 is a columnar artificial chordae.

FIG. 7 provides schematic views and cross-sectional views of the frame according to Embodiment 1 provided with a covering membrane and a prosthetic valve leaflet. FIG. 7a 1 is a perspective view of the frame with an outer covering membrane; FIG. 7a 1 is a front view of FIG. 7a 1; FIG. 7a 3, FIG. 7a 4, FIG. 7b 1, and FIG. 7b 2 show cross-sectional views of a frame provided with a covering membrane and a prosthetic valve leaflet during different status of systolic and diastolic duration, FIG. 7a 3 and FIG. 7a 4 show the double-leaflet valve leaflet, FIG. 7b 1 and FIG. 7b 2 show the single-leaflet valve leaflet; FIG. 7c 1 shows the cross-sectional view of the single-leaflet leaflet held by the connector, FIG. 7d 1 shows the double-leaflet leaflet held by the connector; arrows indicates the direction of blood flow; 701 is the frame body, 711 and 741 are the roots of valve leaflet, 712 and 742 are free edges of valve leaflet, 721 is a single-leaflet valve leaflet body, 751 is a double-leaflet valve leaflet body, 731 is the outer covering membrane, 732 is the inner covering membrane, 761, 762 and 763 are connectors.

FIG. 8 provides overall schematic views of the device for treating mitral valve regurgitation according to Embodiment 1. FIG. 8a is a schematic view of the device when the supporting rod is a straight rod; FIG. 8b is a schematic view of the device when the supporting rod is bent at an angle of θ; wherein, 811 is a cover, 812 and 821 are frames, 813 is a straight supporting rod, 814 is a positioning sleeve, 815 is an apex snap ring, 816 is a fixation plug, 817 is a plug, 822 is a supporting rod bent at an angle of θ, and the broken line indicates a direction of a long axis of the frame.

FIG. 9 is a schematic view of a frame according to Embodiment 1 and supporting rod linker which are integrally formed, wherein 911 is the frame part and 912 is the supporting rod part;

FIG. 10 are schematic cross-sectional views at the cardiac short axis plane of the frame according to Embodiment 2; 101 to 106 in FIG. 10a is a schematic view of different shapes and a combination of shapes; FIG. 10b is a schematic cross-sectional view of the frame in relationship to native valve leaflets when cross-section is 105, wherein 2.2 is anterior leaflet, 2.3 is posterior leaflet, 111 and 112 are the portions of native valve leaflet that fit the frame 114, and 113 is the possible coaptation area of native leaflets on the frame.

FIG. 11 is a schematic view of an anchoring device according to Embodiment 3, in which 132 is an intra-atrial lattice-shaped anchoring cage, 133 is a lattice frame, and 134 is an intra-ventricular linker supporting rod.

FIG. 12 is a schematic view of a device for treating tricuspid regurgitation according to Embodiment 4, in which 141 is a frame, 142 is a tri-leaflet prosthetic valve leaflet, and 143 is a meshed supporting rod.

DETAILED DESCRIPTION

Certain specific details are set forth herein the following description and drawings, in order to understand various embodiments of the present disclosure. A person skilled in the art will understand that they are capable of practicing other embodiments of the present disclosure without one or more of the details described herein. Accordingly, the scope of the appended claims is not limited in anyway by such details.

As used herein, the term “proximal end” shall refer to the end that is closer to the atrium or in the atrium, while “distal end” shall refer to the end that is closer to the ventricle or in the ventricle. The term “inflow end” shall be the end that blood flows in and the “outflow end” shall be the end that blood flows out.

The term “sheath” may also be described as “catheter”. The term “lattice structure” may also be described as a “network structure”, meaning a structure having meshes or holes.

The term “cardiac long axis” shall refer to the axis from the atrium to the ventricle through the native valve orifice, and the “cardiac short axis” shall refer to the axis perpendicular to the cardiac long axis.

The patient or subject to be treated according to the disclosure, i.e., the patient or subject having a cardiac valve regurgitation, is a mammal, preferably a human.

The device of the disclosure and its implantation method seek to reduce or block the amount of blood flowing from the ventricle to the atrium during the cardiac systole period to ensure a sufficient amount of blood flowing from the atria to the ventricle during the cardiac diastole period and to reduce thrombosis. The device of the present disclosure can reduce or eliminate the size of leakage opening of the native valve, allowing the valve to function in a condition of little or no regurgitation. In some embodiments, by positioning the device for treating regurgitation between the leaflets of mitral or tricuspid native valve, the leakage openings between the native valves are closed or plugged in when native valve is closed. In the embodiments described in the present invention, the device for treating regurgitation does not reduce the effective blood flow area during diastole, thus ensuring a sufficient amount of blood flowing from the atrium to the ventricle.

The following description refers to FIGS. 1 to 12. Those skilled in the art will recognize that, the drawings and the description of the drawings are directed to various embodiments of the disclosure, and are not intended to limit the scope of the appended claims to the accompanying drawings and/or description of the drawings, unless required in the context.

Embodiment 1

A device for treating mitral regurgitation, comprises a frame and an anchoring device with the anchoring device being connected to the frame.

Frame

The frame is placed in the native mitral valve leakage gap by an anchoring device when the mitral valve is closed, the frame being expanded at the gap, the native valve leaflets being in close contact with the outer surface of the frame when it is closed. The frame has an inflow end and an opposite outflow end. The frame acts as a supporting structure for a prosthetic valve in the frame and makes the entire device compressible and expandable.

In vitro, the device is compressed into the catheter, and upon reaching a predetermined position of the native valve orifice, the device is pushed out to self-expand back to its originally designed expanded state and is anchored by the anchoring device.

The outflow end of the frame is preferably tapered relative to the inflow end, which occupies less space and facilitates the application of tensile force on the outflow end to retrieve the frame back to the catheter. The tapered shape provide flexibility for placement of the prosthetic valve to best reduce regurgitation.

The shape of the frame mesh is not unique, can be any shape that allows blood flow to go through and is compressible and expandable. As shown in FIG. 4, the frame of the present embodiment is a lattice structure with rhombic meshes and/or irregularly-shaped meshes with an arcuate edge. The frame is made of an elastic alloy material, such as a nickel-titanium alloy, etc., by an integrated laser cut technique. Preferably, the mesh opening at the outflow end of the frame is larger, which reduces the blood outflow resistance for better hemodynamics. As shown in FIG. 4a 1, the mesh density of the frame with rhombic meshes gradually decreases from the inflow end to the outflow end, and the meshes near the outflow end are of irregular shape with arcuate edges.

Due to biological variance, the length, width and heights of the frame can vary to fit the actual anatomy of the patient. The length 411 of the frame from the inflow end (proximal end) to the outflow end (distal end) is 20-80 mm, more preferably the length of the frame is 35-65 mm, and may also be set at 25 mm, 30 mm, 40 mm, 50 mm, 60 mm and 70 mm. The maximum frame height 412 of the cross-section at the cardiac short axis plane of the frame is 30 mm, the height is in a range of 0.1-30 mm, 5-25 mm, 10-20 mm or 5-15 mm; the maximum frame width 413 is 50 mm; the width is in a range of 0.1-50 mm, 1-45 mm, 5-40 mm, 10-35 mm, 15-30 mm, 30-45 mm, or 8-25 mm. A relatively large size is suitable for adult patients, a relatively small size is suitable for juvenile patients, and a much smaller size is suitable for infant and children patients. A width of the cross-section is preferably more than 200% of the height. In one example of this embodiment, the frame shown in the drawings has a width of 38-42 mm, a height of 7-9 mm, and a length of 50-60 mm.

As shown in FIG. 4a 4, the shape of the cross-section at the cardiac short axis plane is a combination of rectangular in the middle, semi-circular on two opposite ends, and is symmetrical. The shape of the cross-section can change continuously or in stages from the inflow end to the outflow end of the frame. The size, such as height and width of the cross-section, in example of the continuous change and is decreased or increased continuously. For example, along the cardiac long axis, the area of cross-section at different length location is continuously deformed and shrunk, until it is changed to be an elliptical or circular shape with a smaller area at the outflow end. The change in stages refers to the shape of the cross-section being maintained along a length in a particular shape, and then the shape is gradually changed and area is reduced along the cardiac long axis to the outflow end of the frame.

As shown in FIG. 4a 2, the shape and area of the cross-section of the frame remain unchanged from the inflow end to the midpoint of the whole frame, and then the area is decreased and shape is changed gradually and continuously, with the frame mesh expanding continuously till the outflow end of the frame, the shape of cross-section is gradually changed into a smaller circle, which connect to the anchoring device.

The tapered cross-section of the frame may have a broader range of applications, making it possible for the same device to be used for patients of different ages or types of illness. For example, by implanting the device of the present disclosure, by adjusting the position of the frame at the orifice, the varying cross-section can correspond to different orifice gaps to bring the native valve leaflets coaptating to the frame more closely, and prevent regurgitation more effectively.

In the present embodiment, all of the reinforcement are provided inside the frame as shown in FIGS. 5a 1 and 5 a 2; the reinforcement is provided in the middle of the frame or in the cardiac long axis direction and is to facilitate compression of the frame and keeping the symmetry of frame. The reinforcement serves as a structural enforcement for the frame and may be integrally formed with the frame, or it may be formed separately and connected to the frame through welding, riveting and suturing. The reinforcement is preferably of the same material as the frame. The reinforcement can be solid or in a mesh structure.

Prosthetic Valve Leaflets

The prosthetic valve leaflets is to maintain the unidirectional flow of blood inside the frame. During systole, the native mitral valve leaflets coaptates on the outer surface of the frame; and the prosthetic valve leaflets in the frame are also closed, effectively preventing regurgitation. During diastole, the native mitral valve leaflets open, the frame will stay in the original mitral orifice supported by the anchoring device connected thereto, the blood flows from the atrium to the left ventricle between outside of the frame and the native valve leaflets, and the prosthetic valve leaflets inside the frame also open to allow the blood flow from inside the frame, to prevent mitral stenosis.

In the schematic drawings where a prosthetic valve leaflet body 621 is directly sewn on the frame as shown in FIGS. 6a 1 and 6 a 2, the root 611 of the prosthetic valve leaflet is hermetically connected and fixed to the frame, and the leaflet free edge 612 can open or close as the blood flow direction changes. Both the leaflet root 611 and the free edge 612 may be completely, partially attached or not attached to the frame. If the cross-section of the frame is relatively narrow and the ratio of the longest axis to the shortest axis is greater than 2:1, then the number of prosthetic valve leaflets are preferably one, two or four. In the case of multiple leaflets, the inter-leaflet connection can be attached to the lattice of the frame. The other edge portions of the prosthetic valve leaflet will be left free, allow valve leaflets to open; during systole the leaflets close in a semilunar shape so the edges can be completely coaptate.

In this embodiment, the free edge of the prosthetic valve leaflet is extended by a connector, which may be fabricated by cutting an animal valve and/or pericardium, as shown in FIGS. 6b 1-6 b 4. One end of the artificial chord 622 is connected to the free edge of the prosthetic valve leaflet, and the other end is connected part of the frame proximal to the root of valve leaflet. The connector serves to distribute closing load more evenly and to prevent potential leaflet prolapse.

The position of the prosthetic valve leaflets can be anywhere applicable in the frame (top, middle, bottom in the long axis direction, for example). In this embodiment, the preferred prosthetic valve leaflets are bovine pericardium or porcine aortic valve.

Covering Membrane

The covering membrane has the function of providing the sealing of the frame of the lattice structure and preventing blood from flowing into the atrium from the mesh of the frame as leakage around the prosthetic valve.

The covering membrane covers at least a portion of the inner and/or outer surfaces of the frame. The covering membrane may completely cover the inner and/or outer surface of the frame, with some opening left for blood flow to pass through along the long axis.

The covering membrane may be a connection site between the frame and the prosthetic valve leaflets; preferably over the outer surface of the frame, more preferably, over both inner and outer surface of the frame. The inner covering membrane covers at least the area where the prosthetic valve leaflets coaptate. As shown in FIG. 7, FIGS. 7 a 3 and 7 a 4 show the opening and closing of the mono leaflet valve in the frame along the blood flow direction. FIGS. 7 b 1 and 7 b 2 show opening and closing of the bi leaflet valve in the frame as the blood flows. The inner covering membrane 732 is placed on the inner surface of the frame near the ventricle.

The root 711 of the mono leaflet valve and the root 741 of the bi-leaflet valve can be sewn on the covering membrane and/or the frame. As shown in FIGS. 7a 3 and 7 b 2, during diastole, blood flows through the open valve leaflets; during systole, the valve leaflets close as shown in FIGS. 7a 4 and 7 b 1, preventing regurgitation inside the frame.

Preferably, when the prosthetic valve leaflets are held by the connector serving the function as an artificial chorda, FIG. 7c 1 shows that the connector 761 holds the free edge of the mono leaflet valve leaflet 721 during diastole; FIG. 7d 1 shows that the connector 762, 763 hold the free edge of the bi-leaflet valve leaflet 751. The illustrated connectors have structure such that it does not restrict the flow of blood during diastole yet provide adequate tension in the free edge of the leaflets to prevent leaflet prolapse and tear of leaflet or connector. The connector can be sutured on the covering membrane.

In this embodiment, the covering membrane is connected to the frame by suturing; the material of the covering membrane is preferably a kind of biocompatible material that does not cause blood to coagulate, and may include polytetrafluoroethylene, nylon, polyester, polyurethane, polyester, animal valves and/or pericardium, such as pigs, bovine valves and/or pericardium.

The length of the covering membrane from the inflow end to the outflow end along the frame is less than or equal to the length of the frame in a length range of 5-60 mm, furthermore, 10-50 mm, 15-40 mm, 20-35 mm.

Anchoring Device

The anchoring device includes a linker and an anchor; and the anchor is connected to the frame by the linker. During diastole, both of the native mitral valve leaflets and the prosthetic valve leaflets in the frame are open and the frame is free to translate within the valve orifice supported by the anchoring device so that there is minimal resistance to blood flow during diastole, and blood flow can simultaneously wash both inside and outside of the frame, thus reducing the potential of thrombosis.

In this embodiment, as shown in FIG. 8, the anchoring device includes a linker supporting rod 813, a positioning sleeve 814, an anchor apex snap ring 815, a fixation plug 816 and a plug 817. The proximal end of the supporting rod 813 is connected to the outflow end of the frame 812; the apex snap ring 815 is fixed in the intra-ventricular apex position as shown in FIG. 8b , or close to the apex between two papillary muscles; the positioning sleeve 814 is fixed on the apex snap ring; the distal end of the supporting rod 813 is connected to a positioning sleeve 814, and the sleeve can be moved relative to the supporting rod and fixed again. By adjusting the distance of relative movement, the whole length of the connector can be adjusted. The fixation plug is located outside the apex for positioning the apex snap ring. The plug shown is mounted on the outside of the positioning bushing to further assist the positioning and to improve the seal of the device to prevent blood in the ventricle from leaking through the apex snap ring. A puncturing tip is arranged at the distal end of apex snap ring. The above connection may be a threaded connection or a snap-in connection.

The supporting rod may be a tube weaved from Ni—Ti wires or one piece tube with side openings, and the surface can be covered with a blood-compatible material such as PTFE.

In other embodiments, the linker and anchor are connected by an elastic or hinged joint; the anchoring device allows swinging or rotating the frame at the orifice position of the native valve to accommodate the different shapes and position of orifice of a leaky valve.

During diastole, the axial load generated by shear stress in the forward blood flow of the frame is rather small, and can be supported by the anchoring device; the frame is free to translate within the annulus. When the anchoring device is placed at the apex, the pressure differential force on the frame during systole is transmitted to the apex in the direction ventricular contraction. This may help to restore the left ventricular function.

When the supporting rod is straight, the anchoring device is preferably placed between the papillary muscles. If the anchoring device is placed at the apex, the supporting rod preferably has a bend toward the anchoring element, and the angle from proximal end to the distal end is defined as the angle θ, as shown in FIG. 8b 2, wherein the bending angle θ of the supporting rod 822 ranges from 0 to 30 degrees. The θ angle range may also be 0.1-25 degrees, 0.5-20 degrees, 5-15 degrees, depending on anatomy of patients and placement of the anchor. The supporting rod is elastic, which allows compression into the sleeve.

Preferably, a “visualization element” may be attached or placed on the device of the present disclosure to monitor the proper placement of the device, for example the visualization element may be a radiopaque marker comprising any suitable material, such as, for example, gold, tantalum, or platinum.

More preferably, the frame and the supporting rod of the embodiment can be integrally manufactured from one material and process, such as Ni—Ti tube laser cutting. The supporting rod part can be in the shape of a tube with meshes, which can be more manufacturing friendly as shown in FIG. 9.

The device of this embodiment can be implanted with a minimally invasive procedure. Such implantation includes the following steps:

A, incision on the chest is made near the apex position of the heart;

B, in vitro, assemble the frame, the supporting rod connected to the frame, and the positioning sleeve, compressed and placed into the puncturing catheter, an apex snap ring is assembled outside of the catheter, wherein the tail of the apex snap ring is connected to a handle;

C, the above puncturing catheter is moved through the left chest incision to reach the apex and penetrate into the left ventricle and by maneuver through the handle, the apex snap ring is then placed at the apex;

D, push the frame and the positioning sleeve out from the puncturing catheter, to adjust the relative position of the positioning sleeve to the supporting rod; withdraw the puncturing catheter, the fixing cap is mounted on the lower end of the apex snap ring, then withdraw the handle;

E, the cap is mounted on the exterior end of the positioning sleeve, and the chest incision is closed.

The device for treating mitral regurgitation provided by the embodiment and the implantation method can effectively treat mitral valve regurgitation. The device can be accurately and firmly positioned, and can move along with the apical movement. It does not cause adhesions with the native annulus, and does not block blood flow. The device can be retracted, and the procedure is minimally invasive.

Embodiment 2

As shown by 101 to 106 in FIG. 10, the shape of cross-section in the short axis plane of the frame is an irregular combination of arcuate edges and may continuously vary from the inflow end to the outflow end of the frame, so as to fit different gaps between native valve leaflets during systole.

As shown in FIG. 10, is the cross-section of the frame in relationship to the native valve leaflets, in which 2.2 is the anterior leaflet and 2.3 is the posterior leaflet. In this case, the distribution of the gap 116 in the mitral regurgitation is not uniform; The gap is narrow in the middle, while the gaps at both sides may be irregular and may become rather large. Different from Embodiment 1, the shape 105 of the preferred cross-section of the embodiment of the present embodiment assumes a crescent-like shape. Its central portion has an arc with a height narrower than its two ends, and its two ends are rounder and larger. When the frame is in contact with the native valve leaflets, the coaptation line has a certain curvature. In the figure, 111 and 112 are the possible contact areas of the leaflets to the frame 114, and 113 is a possible contacting line or so called coaptation line. This allows almost complete coaptation of native valve leaflets on the frame in this embodiment, thus effectively reduce mitral insufficiency.

Embodiment 3

Different from Embodiment 1, the anchor further includes an anchor mechanism involved with a lattice structure arranged inside the atrium, similar to the shape of a cage. The shape of the anchor can be adapted to the anatomy of the left atrium; so to allow positioning the frame at the desired location. The frame may be a lattice structure in a cylinder. When the inner diameter of the cylinder is large enough, it may displace the native valve to become a valve replacement. The distal end of the anchoring cage is connected to the inflow end of the frame, and may be connected by an elastic metal wire, such as a Ni—Ti alloy wire. The anchoring device, with elements including the linker supporting rod and the anchor as shown in the Embodiment 1, and the like, may be placed in the ventricle at the same time. As shown in FIG. 11, the anchoring device includes an intra-atrial lattice-like anchoring cage 132, a cylindrical lattice frame 133, and an intra-ventricular linker supporting rod 134. In this case, both the anchoring device and the frame can be integrally prepared by a laser process.

Embodiment 4

This embodiment is a device for treating tricuspid regurgitation, comprising a frame and an anchoring device, the anchoring device being connected to the frame. The anchoring device refers to the anchor and the supporting rod linker provided in the right ventricle according to the first embodiment. As shown in FIG. 12, the valve leaflets in the device for treating tricuspid regurgitation are preferably tri-leaflet prosthetic valves, and the cross-section of the frame is preferably circular. The supporting rod may be of a lattice structure.

While the disclosure has been described in terms of particular embodiments and applications, based on the teachings, one of ordinary skill in the art may implement alternative embodiments and make additional modification without departing from the spirit of the disclosure or beyond the scope of the disclosure. Accordingly, it should be understood that the drawings and descriptions are provided herein as examples to assist in understanding the present disclosure, and should not be used to limit the scope thereof. 

1. A device for treating valve regurgitation, characterized in that it comprises a frame and an anchoring device, the anchoring device is connected to the frame, the frame is expandable and compressible, having an inflow end and an opposite outflow end, a prosthetic valve, which opens and closes in the blood flow is provided inside the frame; and the anchoring device is capable of positioning the frame in an expanded state at the native heart valve orifice.
 2. The device for treating valve regurgitation according to claim 1, characterized in that, the frame has a covering film on at least part of the inner and/or outer circumferential surface of the frame; the covering film at least covers the outer circumference of the frame at the junction of the valve leaflets of the frame.
 3. The device for treating valve regurgitation according to claim 1, characterized in that, the frame has an expandable and compressible lattice structure with rhombic and/or hexagonal meshes, or the lattice structure is made of irregular meshes with curved edge by cross-wrapping straight and arc lines.
 4. The device for treating valve regurgitation according to claim 1, characterized in that, reinforcement is provided in at least part of an interior of the frame; the reinforcement includes a plate-like member, a column-like member, or a plate-like member or a column-like member with a lattice structure.
 5. The device for treating valve regurgitation according to claim 1, characterized in that, the length in the cardiac long-axis direction from the inflow end to the outflow end of the frame when the frame is expanded to 20-80 mm.
 6. The device for treating valve regurgitation according to claim 1, characterized in that, a cross-section at the cardiac short axis plane of the frame, when the frame is expanded, has a thickness of 3-30 mm and a width of 1-50 mm.
 7. The device for treating valve regurgitation according to claim 1, characterized in that, a cross-section at the cardiac short axis plane of the frame, when the frame is expanded, has a shape including a circular, oval, rectangular or rounded rectangle, crescent or rounded crescent, dumbbell-shaped, a combination of rectangle in the middle with semi-circular on two opposite ends, a trapezoid or rounded trapezoid, and their combined shapes, or an overall shape similar to crescent as a whole with arc in the middle and thicker in the middle than in two ends.
 8. The device for treating valve regurgitation according to claim 1, characterized in that, shape of a cross-section at the cardiac short-axis plane of the frame, when the frame is expanded, changes continuously or in stages from the inflow end to the outflow end of the frame.
 9. The device for treating valve regurgitation according to claim 2, characterized in that, the covering film is connected to the frame by means of sintering, welding, gluing or sewing; the covering film covers outer and inner circumference of the frame at the junction of the valve leaflets of the frame.
 10. The device for treating valve regurgitation according to claim 2, characterized in that, the material of the covering film comprises a blood-compatible material, an artificial blood vessel material, an animal valve, an animal pericardium, and a polymer.
 11. The device for treating valve regurgitation according to claim 1, characterized in that, the device has a prosthetic valve inside with which the prosthetic valve leaflets include a uni-leaflet valve, a bi-leaflet valve, a tri-leaflet valve or a tetra-leaflet valve; the valve leaflet is connected to a frame having a lattice structure by means including sewing or gluing.
 12. The device for treating valve regurgitation according to claim 2, characterized in that, end of the prosthetic valve leaflet is connected to the frame and/or the covering film on the frame, the free edge of the prosthetic valve leaflet is connected to the frame and/or the covering membrane through a connector; structure of the connector includes strip, filament, sheet, column, net, or a combination thereof, can be an integral part of the leaflet or separate element.
 13. The device for treating valve regurgitation according to claim 1, characterized in that, the material of the frame comprises a metal material, polymer material or memory alloy material; the material of the valve leaflet includes animal valve, animal pericardium, artificial chordae, polymer, and artificial blood vessel material.
 14. The device for treating valve regurgitation according to claim 1, characterized in that, the anchoring device comprises a linker and an anchor; the anchor is connected to the frame through the linker; the anchor may be arranged on the valve annulus, at apex or between the papillary muscle near the apex, or a stent and/or an intra-tissue anchor arranged on the surface of inner wall of ventricle, an open cup-shaped stent arranged in the inner chamber of atrium, on the surface of inner wall of atrium, a frame having a lattice structure arranged in the inner chamber of atrium, or a combination of the above anchors.
 15. The device for treating valve regurgitation according to claim 14, characterized in that, a linker is used to connect the anchor and the frame, said linker includes a rod, a wire, a sheet, a column, or a tube, or a combination thereof and the material of the linker comprises metal material, memory alloy material or polymer material.
 16. The device for treating valve regurgitation according to claim 14, characterized in that, the linker and the anchor are connected by an elastic material or a hinge; so to allow the frame to swing or rotate in the native valve orifice.
 17. The device for treating valve regurgitation according to claim 1, characterized in that, the anchoring device comprises a supporting rod, a positioning sleeve, an apex snap ring and a fixation plug; the proximal end of the supporting rod is connected to the outflow end of the frame; the distal end of the supporting rod is connected to the positioning sleeve; the apex snap ring is fixed at the apex or the papillary muscle near the apex; the positioning sleeve is fixed on the apex snap ring; the fixation plug is connected to the apex snap ring and is located outside the apex to position apex snap ring; the positioning sleeve can be moved or slide relative to the supporting rod.
 18. The device for treating valve regurgitation according to claim 17, characterized in that, the supporting rod is provided with a partial bend in a range of 0-30 degrees from the proximal end to the distal end.
 19. A method for implanting the device for treating valve regurgitation according to claim 1, characterized in that, loading in a cannula the expandable and compressible frame after being compressed implanting the expandable and compressible frame into a native valve position through a minimally invasive technique to make the frame reach an expanded state, the frame is positioned in the native valve orifice by means of the anchoring device connected to the frame, such that the native heart valve leaflets coaptate on the outer surface of the frame during systole; compressing the anchoring device into the cannula and implanting it into the heart, either simultaneously with the frame or not; the frame and the anchoring device are configured to be completely retracted or partially retracted by an original implantation method.
 20. A method for implanting a device for treating valve regurgitation, characterized in that, comprising the steps of: A. providing the implanting device of claim 1, wherein an expandable and compressible frame, the linker and the anchor are collectively or partly assembled in vitro, whole assembly or subassembly are configured to be compressed into a puncturing catheter; B. placing a puncturing catheter from the apex position through an incision on left chest into a left ventricle or right ventricle, to a mitral or tricuspid valve orifice, the whole assembly or subassembly is then pushed out, the puncturing catheter is withdrawn. C. attaching the anchor to the apex position. 